Study Finds Trees Are Good for Your Heart


If you want to get a number of benefits out of one health tip, try this: Go plant yourself a tree. Recent science shows that living among trees makes people feel subjectively healthierreduces pollutionboosts mental health—and may also be good for heart health, according to new research. 

A study in the journal Health and Place found that a lack of trees might be a risk to women’s cardiovascular health. The study analyzed health statistics in places where an invasive pest, the emerald ash borer, had decimated the local tree population. The beetle was first discovered to be killing Michigan ash trees in 2002, and has since spread to other states, encompassing 245 U.S. counties in total. 

Using longitudinal data from the Women’s Health Initiative, researchers led by the USDA Forest Service, examined links between tree loss and the cardiovascular events for the 156,000 women in the initiative’s data pool. More than 14,500 post-menopausal women in the sample suffered a heart attack or stroke or died from coronary heart disease during the study period of 1991 to 2010.

The researchers found that even accounting for factors like exercise frequency, women who lived in a county where the emerald ash borer moved in and started killing trees had a 25 percent increased risk of heart disease. 

This study can’t prove without a doubt that living without trees causes heart attacks (maybe some other unexamined environmental factor upped the risk of heart attacks during those years). And it didn’t sample men, about one in four of whom will die of heart disease. However, given the wealth of other studies indicating that trees benefit your health, it wouldn’t be surprising if they also keep your heart healthy, especially because of their stress-reducing effects.

[h/t: Pacific Standard]

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These Are the World's 10 Most Expensive Cities

While Americans in big cities may complain about how expensive the cost of living is, according to a new report, places like New York and Los Angeles don’t even come close to the expense of international cities like Singapore. As Travel + Leisure mentions, The Economist Intelligence Unit’s biannual report on the world’s most expensive cities has named the Asian city-state the most expensive place on Earth to live for the fifth year in a row. No U.S. city even cracks the top 10.

The Intelligence Unit’s survey tracks prices of 160 products and services in cities across the world, including food and drink, clothing, rent, utility bills, transportation, and more. It’s designed to help companies calculate cost-of-living analyses for employees traveling and living abroad, but it also just provides an intriguing snapshot into how the rest of the world lives, and just how expensive your next vacation might be. And, of course, it allows you to feel a little better about your own city. Next time you want to complain about your rising rent, New Yorkers, know that residents of Seoul have to pay 50 percent more than you for groceries.

The prices used in the calculations are converted to U.S. dollars, meaning that the whole thing is tied to how much the dollar is worth—if the euro is worth more than the dollar, you’ll need more dollars to buy things in Paris. A weakening dollar is one reason the report gives for the lack of U.S. cities in the top 10 list, even though American cities are becoming more expensive relative to past years. (New York, currently in 13th place, was in the 27th spot five years ago.)

Without further ado, and with our deepest sympathies to their denizens, here are the top 10 most expensive cities across the world:

1. Singapore
2. Paris, France
2. Zurich, Switzerland
4. Hong Kong
5. Oslo, Norway
6. Geneva, Switzerland
6. Seoul, South Korea
8. Copenhagen, Denmark
9. Tel Aviv, Israel
10. Sydney, Australia

[h/t Travel + Leisure]

19 Must-Visit Stops on Mexico City's Metro

About 5 million people ride the Mexico City subway every day—but most commuters don’t realize how much there is to do and see without ever having to go above ground. From piano stairs to a space tunnel, exploring the attractions hidden within the metro just might be the most fun you can have for 5 pesos (about $0.25 USD). These Mexico City metro stations settle the old question once and for all; it’s both the journey and the destination.


Talisman station (line 4) has a mammoth logo for a reason: Mammoth fossils were unearthed during construction of the metro, and you can see the bones—which date back to the Pleistocene—on display there.


space tunnel at La Raza station
Sharon Hahn Darlin, Flickr // CC BY 2.0

How do you make a long transfer fly by? Transform it into a walk-through space tunnel illuminated by a glow-in-the-dark night sky, the highlight of the science museum located within La Raza station (lines 3 and 5).


Viveros (line 3), a station named for the nearby nursery, is in full flower: It was recently given a jungle makeover complete with imitation palms, jaguars, and snakes to raise awareness for the preservation of southern Mexico’s Lacandon Rainforest.


Complement your day trip to the pyramids at Teotihuacan with a stop at the Pino Suarez station (lines 1 and 2), where you can see a 650-year-old pyramid dedicated to Ehecatl, the Aztec god of wind. Tens of thousands of users go through the station daily, making the pyramid one of the most visited archeological sites in Mexico. (Though it's referred to as Mexico’s smallest archaeological zone, the National Institute of Anthropology and History doesn't consider it a "proper" archaeological zone "due to its size and the fact of being located in a Metro Transport System facility.")


Hidalgo (lines 2 and 3) may be the most miraculous of all of Mexico City’s metro stations: In 1997, someone (possibly a street vendor) discovered a water stain in the shape of the Virgin of Guadalupe in one of its floor tiles. The apparition attracted so many pilgrims that metro authorities eventually had to remove the tile, which is now enshrined just outside one of the exits (follow the signs for Iglesia), near the intersection of Paseo de la Reforma and Zarco. And if you happen to visit this station on the morning of the 28th of any month, you’ll be swarmed with pious commuters carrying figurines of Saint Judas Thaddeus—patron saint of delinquents and lost causes—who is venerated at the nearby San Hipolito Church.


No time to visit the vast National Museum of Anthropology? You can still catch reproductions of Mesoamerican statues at the Bellas Artes (lines 2 and 8) and Tezozomoc (line 6) stops.


miniatures on the Mexico city subway
Randal Sheppard, Flickr // CC BY-SA 2.0

Miniature maniacs shouldn’t miss the scale models of Mexico City’s main plaza at the Zocalo stop (line 2). They depict, in tiny form, the metamorphosis of the capital from the Aztec Templo Mayor to the present-day Metropolitan Cathedral. (And bonus points to anyone who can spot the cat who lives in this station.)


The music-themed Division del Norte station’s (line 3) free karaoke corner draws a crowd gathered to watch fellow riders belt out boleros and ballads on their way to work. The unassuming abuelitas laden with bags from the market always have the most impressive pipes.


piano stairs at Polanco station
Victor.Aguirre-Lopez, Wikimedia Commons // CC BY-SA 3.0

Don’t take the escalators at Polanco station (line 7), because the stairs are a giant musical piano keyboard. Finally, here’s your chance to live out Tom Hanks’s piano dance scene from the movie Big.


The Guerrero stop (lines B and 3) is a tribute to the legends of lucha libre, with costume displays and murals dedicated to 45 of Mexico’s finest masked fighters.


The largest bookshop in Latin America can be found in the long passage between the Zocalo and Pino Suarez stations. The underground emporium known as Un Paseo Por Los Libros sells titles from textbooks to manga and also hosts free workshops, lectures, and movie screenings.


murals in the Mexico City subway
Thelmadatter, Wikimedia Commons // Public Domain

Any visitor to Mexico City should check out Diego Rivera’s murals—but on your way, don’t forget to look up at the murals that decorate many metro stations. Particularly impressive are Guillermo Ceniceros’s ambitious chronicles of art through the history of time on the walls at the Copilco (line 3) and Tacubaya stations (lines 1, 7, and 9). On the kitschier side, see how many famous faces you can pick out in Jorge Flores Manjarrez’s I Spy-style mural of pop stars at the Auditorio stop (line 7).


A museum of caricatures located inside the Zapata stop (line 12) is an homage to Mexican cartooning, including plenty of satirical interpretations of the mustachioed revolutionary who gives the station its name.


If Chabacano station (lines 2, 8, and 9) feels unsettlingly familiar, it might be because it was used as a shooting location for the subway chase scene in the Arnold Schwarzenegger film Total Recall. Legend has it you can still spot splashes of fake blood on the ceiling.


Museo del Metro de la Ciudad de México
ProtoplasmaKid, Wikimedia Commons // CC BY-SA 4.0

Has this metro adventure turned you into a super fan? Do a deep dive at Mixcoac station’s (line 12) sleek Metro Museum, where you can learn even more fun facts about the subway’s 50 years of history while you wait out rush hour.


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